Superheater protecting wall



Nov. 3, 1942. D. M. SCHOENFELD SUPERHEATER PROTECTING WALL Filed Oct'. 21, 1939 2 Sheets-Sheet l IDIJVENTOR flm/al ji. &akuzu/dd REY* D. M. SCHOENFELD 2,300,816

SUPERHEATER PROTECTING WALL Nov. 3, 1 942.

Filed Oct. 21, 1959 2 Sheets-Sheet 2 INVENTOR flag/a 1 1 .filmin/dd RNEY Patented Nov. 3, 1942 'r t'ir ce SUPERH-EATER PROTECTING WALL David M. Schoenfeld, New York, N. Y., assignor to Combustion Engineen'ng Company, Inc., New

York, N. Y.

Application 'October 21, 1939, Serial No. &00,544

4 Clamsa.

The present invention relates to improvements in boilers and particularly to boilers provided with superheaters.

The invention contemplates a boiler having separately fired superheater and boiler furnace chambers so arranged that protection is afforded to the superheater when starting up, providing means for regulating the superheat temperature and allowing operation with production of little or no superheat as sometimes required, particularly for marine purposes. -In these respects the present invention is similar to that disclosed in a copending application filed in my name under Serial No. :300,543 on Oct. 21, 1939. The present invention however embodies further improved means for obtaining the above mentioned objects and will be best understood upon consideration of the following detailed description of several illustrative embodiments thereof when read in conjunction with the appended claims and the accompanying d'awings in which:

Figura 1 is a diagrammatic elevational View, part-ly in section, of one 'form of boiler construction embodying the present invention, the boiler being equipped with a radiantly heated superheater;

Figure 2 is a similar view of a boiler also embodying the invention and provided with both radiant and convection heated superheater surfaces; and

Figure 3 is a similar View of a boiler embodying the invention and equipped with a convection heated superheater.

In the boiler shown in Fig. 1 the steam and water drum extends across the upper part of the boiler and is connected with the water drum Il disposed therebelow by a substantially Vertical bank !2 of generating tubes. The furnace space at the side of bank |2 opposite the boiler offtake |3 is divided by a Wall I 4 to form two separate furnace chamber arranged in superposed relationship, one being a superheater furnace chamber I 5 and the other a boiler furnace chamber !6. However, it should be understood that the functions of the two chambers might be reversed. Individual fuel feeding burners ll are provided for the two furnace chambers.

As shown herein the wall M which extends completely across the furnace space between the front and rear walls is formed by the substantially horizontal portions [8 of generating tubes 20. These tubes are arranged in one or more rows connected to a header ZI located opposite the bank 12 vertically intermediate the drums I 0 and ll and extending transversely across the furnace space and thence upwardly substantially parallel to the bank 1 2 to th steam and water drum li). The horizontal portions !8 of the tubes 20 are so arranged as to preclude the flow of gases thereover from boiler iurnace chamber |6 to superheater urnace chamber 55, as for example by `arranging the tubes in contact, providing them with fins or applying refractory material. The upper or` vertical portions '22 of the tubes 20 that parallel th bank i2 are spaced to 'permit the gases from the superheater furnace chamber !5 to flow to the upper portion of the bank !2, the wall l l bein so located to cause these gasesto flow from the superheated furnace chamber to this portion of the generating bank and at the same time preventing flow of gases from the boiler furnace chamber lt into the superheater furnac chamber !5. The superheater furnace chamber is provided with a, superheater having tubular elements 23 arranged to be radiantly heated. Some of these tubes are arranged in spaced relation in a ro'w closely parallel to the upper vertical portions 22 of the generating tubes 20.

The arrangement illustrated in Fig. 2is generally similar to that described above but some of the superheater tubes at 24 are radiantly heated by fuel burned in chamber I 5 and other superheater tubes 25 are disposed adjacent the Vertical portions 22 of the generating tubes so as to be convection heated by gases passing from the superheater chamber !5 to the upper portion of the bank !2.

In the form illustrated in Fig. 3 the superheater furnace chamber !5 has only the superheater tubes 26 located in the path of gases on their way from chamber !5 to the upper portion of bank 12. As shown the upper vertical portions 22 of generatin tubes 20 are arranged in at least two rows spaced suffciently far apart as to permit the superheater tubes 26 to be mounted therebetween.

It will be noted that in the several forms of the invention described herein the wall |4 formed by the horizontally inclined portions 18 of the tubes 20 functions to prevent gases and radiant heat from the boiler furnace chamber [6 substantially heating the superheater tubes and is so located as to direct gases from the superheater furnace chamber !5 to the upper portion of the generating bank !2 without passing through any part of the boiler furnace chamber !6. consequently, when starting up the boiler steam may be generated without deleteriously afiecting the superheater elements. The provision of separate fuel feeding means for the two furnace chambers arranged as described above permits the boiler to be operated without; production of superheat when desired and further enables the superheat temperature to be controlled by regulating the burners for the superheater chamber [5 regardless of changes that may be required in the firng rate for the boiler furnace chamber IG as steam demand fiuctuates.

What I claim is:

1. In a boiler having upper and lower drums interconnected by a bank of generating tubes and means defining a furnace space at one side of said bank; a header extending across the furnace wall opposite said bank in a position substantially midway between said drums; other generating tubes connecting said drum and header and having substantially horizontal portions extending transversely of said furnace space for dividing it vertically to form a superheater urnace chamber and a boiler furnace chamber disposed in super- 'imposed relation; individual fuel feeding means for said chambers; superheater tubes disposed at the superheater furnace chamber side of said space dividing tubes so as to be heated by fuel burned in said chamber; and baiile means along the horizontal portions of said space dividing tubes for precluding flow of gases from said boiler furnace chamber to said superheater furnace chamber.

2. In a boiler having upper and lower drums interconnected by a bank of generating tubes and means defining a furnace space at one side of said bank; other generating tubes having substantially horizontal portions disposed generally normal to said bank and arranged in one or more rows extending transversely of said space for dividing it into a superheater furnace chamber and a boiler furnace chamber; individual fuel feeding means for said chambers; radiant superheater surface heated by fuel burned in said 'superheater furnace chamber; and bafiie means extending along said horizontal tube portions between said superheater surface and said boiler furnace chamber to a point adjacent said bank for precluding gas flow from said boiler urnace over said superheater surface and for directing gases from said superheater urnace chamber to said generating bank without flowing through said boiler furnace chamber.

3. In a boiler having a bank of generating tubes and means defining a furnace space adjacent said bank; bafiie means disposed generally normal to said bank and extending therefrom across said space to the oppo'site side thereof for dividing it to form a superheater urnace chamber and a boiler furnace chamber; a superheater in said superheater urnace chamber; one or more rows of spaced generating tubes connected into the boiler circulation system having portions of substantial length extending alongside said bank between the latter and said superheater tubes to form a side of said superheater furnace chamber, the portions of the tubes alongside said bank being so positioned as to be contacted by gases only from said superheater furnace chamber; and separate fuel burning means for said chambers.

4. In a boiler having a steam and water drum connected by a bank of generating tubes with a water drum disposed therebelow and means defining a furnace space at one side of said bank; other generating tubes arranged in one or more rows having generally vertical portions of substantial length extending parallel and closely adjacent to part of said bank and other contiguous generally horizontal portions extending transversely of said space for dividing it to form a superheater furnace chamber and a boiler furnace chamber; individual fuel feeding means for said chambers; baffle means along said horizontal tube portions for precluding gas flow from said boiler furnace chamber into said superheater furnace chamber and for directing gases leaving the superheater furnace chamber over said vertical portions of said other generating tubes, said vertical tube portions being spaced apart and contacted by gases only from said superheater furnace chamber; and superheater tubes disposed at the superheater furnace chamber side of said space dividing tubes so as to be heated by fuel burned in said superheater furnace Cham ber.

DAVID M. SCI-IOENFELD. 

